Age resisting process for rubber and age resisting rubber compound



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Patented Mar. 1, 19 32 S TE PATENTO-FHCE mom) A r vronzron; or men, 10 5 AGE msrsmmefricocnfss F03 RUBBER AND AGE nnsrs'riire' RUBBER comcnnn No Drawing.

My inyention relatesto rubber orrubben like compounds and more particularly to those having incorporated therein, or applied.

thereto, an. anti oxidant',l whereby the aging qualityof the comp ma materially enhanced, and to a process for retarding the a in of such comounds. D i

I have discovered; that organic chemical When incorporated into a rubber or rubber; i like compound 'priorfto] the fvulcanization. thereof, or when'appliedfto' a vulcanized ar-' ticle, materially retardj deterioration due to] oxidation. i

There a'rela greatjnumber of such compounds which function as antioxidants and in general they may be represented "by the following general chemical constitution :1;

In the above representation of the constitutional formula, the chemical radicals represented byR (a) and R(b) may be any'ofthe Application filed Ju1y23, 1930.,- Se ria1 No. 470,225."

l The chemical radical represented by Rmay beany of the following chemical groups or their equivalents: H, CH CH CH 5201 5, C113 aliphatic, aromatic or mixed aliphatic-ar0'-- dehydes. When this methodof preparation is employed the; formation may be indicated by the following representation:

Other methods of preparation beemf ployed, the specific ring formation possessing I antioxidant propertiesnot dependent" upon 7 the particularmethodj of formation.

. One of the typical members 'ofthi's' class of materials is, for simplicity, denoted asmeth- V ylene BB di (phenyl amino) ethyl ether, theprobabl'e formula b'eingz p v CH2 -;IR2C/, I T C H5 7 n'zc i j fN+oam For many purposes, thismaterial be the crude-product obtained by heating ani line'andtBB dichlor-ethyl ether, and'whl'ch repared by the reaction of formaldehydeon contains in addition to BB di (phenyl at amino) ethyl ether, a certainquantity of N- phenyl morpholine and other products. hen this method is employed the material may be prepared in the following manner Aniline (372 pounds) is heated with BB dichlor ethyl ether (143 pounds) at a temperature of approximately 200 centigrade until reaction is complete. The reaction product is then treated with a relatively large quantity of hot water to extract the aniline hydrochloride content. The residual oil, amounting to about 200 pounds is then treated with approximately pounds of 40% formaldehyde solution. Due to the reaction being exothermic, considerable heat is evolved. The contents of the vessel are then'heated at 100 centigrade for about three hours to carry the reaction to completion. After separation of the water and cooling, the reaction product solidifies to a soft solid," It is thenready for use. y While in the above example,'I have given the preferred method of manufacture, it is also possible to obtain valuable products by using different ratios of BB dichlor ethyl etherand aniline. Inother words, it is pos sible to use only two or three mole of aniline.

per mol of BB dichlor ethyl ether and it is also possible to use considerably lower tem peratures of reaction. V If desired, the product obtained by heating aniline and BB dichlor ethyl ether may be purified by eliminating morpholine' derivatives prior to the reaction with formaldehyde. I p

Other similar materials, herein referred to, may be prepared in like manner. While it is considered that the above re actions take place in the manner indicated, I do not wish to be bound by the chemical theories herein contained but desire to be protected by Letters Patent on the ring compounds obtained from the material prepared by heating BB dichlor ethyl ether with amines and by the material prepared I mean the semi-purified product containing several ingredients or the purified product from which some of the by-products, such as Ethylldene BB dl (phenyl amino) ethyl ether Butylidene BB cli (phenyl amino) ethyl ether Benzylidene BB di (phenyl amino) ethyl ether Furfur BB cli (phenyl amino) ethyl ether Methylene BB di (ortho tolyl amino) ethyl ether Ethyl dene BB 61 (ortho tolyl amino) ethyl ether Butylulene BB di (ortho tolyl amino) ethyl ether Benzylidene BB di (ortho tolyl amino) ethyl ether Furfur BB rli (ortho tolyl amino) ethyl ether Crotylidene BB di (ortho tolyl amino) ethyl ether Methylene BB di (para tolyl amino) ethyl ether Butyl deneBB (ll (para tolyl amino) ethyl ether Ethylidene BB di (para tolyl amino) ethyl ether Furfur BB (11 (para tolyl amino) ethyl ether Benzylidene BB di (paraytolyl amino) ethyl ether Methylene BB cli (xylyl amino; ethyl ether Ethylidene BB di (xylyl amino ethyl ether Butylidene BB cli (xylyl amino) ethyl ether Benzylidene BB di (xylyl amino) ethyl ether Furfur BB di (xylyl amino) ethyl ether Methylene BB cli (alpha naphthyl amino) ethyl ether Ethylidene BB di (alpha naphthyl amino) ethyl ether Butylidene BB di (alpha naphthyl amino) ethyl ether Benzylidene BB di (alpha naphthyl amino) ethyl ether Furfur BB (1i (alpha naphthyl amino) ethyl ether Methylene BB rliamino ethyl ether Ethylidene BB (liamino ethyl ether Butylirlene BB diamino ethyl ether Benzylidene BB (liamino ethyl ether Furfur BB (liamino ethyl ether Methylene BB di (beta naphthyl amino) ethyl ether Ethylidene BB di (beta naphthyl amino) ethyl ether Butylidene BB di (beta naphthyl amino) ethyl ether Benzyliclene BB 1i (beta naphthyl amino) ethyl ether Furfur BB" di (beta naphthyl amino) eth 1 ether Heptylidene BB (1i (beta naphthyl amino ethyl ether Methylene BB di (methyl amino) ethyl ether Ethylidene BB cli (methyl amino) ethyl ether Butyllden-e BB (li methyl amino) ethyl ether Benzylidene' BB di (methyl amino) ethyl ether Furfur BB di (methyl amino) ethyl ether Crotylidene BB di (methyl amino) ethyl ether t1Methylene B (phenyl amino) B (ortho tolyl amino) ethyl Crotylirlene B (phenyl amino) B (ortho tolyl amino ethyl ether I Ethylidene B (phenyl amino) B (ortho tolyl amino) ethyl ether V Butyl ene B (phenyl amino) B (ortho tolyl amino) ethyl ether Benzylidene B (phenyl amino) B (ortho tolyl amino) ethyl ether i Methylene BB (11 (ethyl amino) ethyl ether I-Ieptyliclene BB di (ethyl amino) ethyl ether Crotylidene BB di (ethyl amino.) ethyl ether EthylideneBB di (ethyl amino) ethyl ether Benzylidene BB di (ethyl amino) ethyl ether Methylene B (xylyl amino) B amino ethyl ether Butylldene B (xylyl amino) B amino ethyl ether Crotyliuene B (xylyl amino) B amino ethyl ether Ethylitlene B (xylyl amino) B amino ethyl ether Benzylldene B (xylyl amino) B amino ethyl ether l-Ieptyhdene B (xylyl amino) B amino ethyl'ether tlMethylene B (phenyl amino) B (methyl amino) ethyl e eflliotylidene B (phenyl amino) B (methyl amino) ethyl etllilli tylidene B (phenylvamino) B (ethyl amino) ethyl etllgtrhyliclene B (phenyl amino) B (methyl amino) ethyl Ill3eg nzylidene B (phenyl amino) B (methyl amino) ethyl etlileieptylidene B (phenyl amino) B (methyl amino) ethyl The above materials areonly indicative of the wide range of compounds which function in carrying out this invention. V

While the materials cited above are the free bases it is also possible to use salts or soaps of these materials formed .from weak acids, withoutmaterially affecting the antioxidant value.

As examples of carrying out the invention the following are typical:

In all of the following examples, tensil means tensile strength at break in pounds per square inch; elongation or elong means elongation at break in percent; and the cure is given in minutes at pounds steam pressure per square inch.

, Example 1 The use of methylene di. (phenyl amino) ethyl ether in a rubber stock accelerated with diphenyl guanidine is illustrated in this example. The test was carried out on the formaldehyde reaction product obtained from the crudeproduct prepared by heating BB dichlor ethyl ether (1 mol) with aniline (4 mols) and removing the aniline hydrochloride- The composition of the rubber stock is as follows Stearic acid"-.. 1.00 Carbon black l 2500 Oil 5.00 Zinc oxiclew u 10.00 Sulphur 2.25 Diphenyl guanidiner; 0.40

Two stocks were mixed, one exactly like the recipe, and the other the same except for the addition of 1.5% of the antioxidant.

After vuloaniiation, the two rubber stocks were tested for aging qualities by the usual hot oven and oxygen bomb methods. 3

The results areas follows: I p l Compound A r Compound-B'- Days in oven at C. Antioxi- Antioxi- Without dant 1.5% dant tensil elongatensil elo nga-.

" tion' CURE so' x ioaf I I OriginaL v 3670" at '3840 69b 2 days 3895 .610. .4040 680 7 days. 2630 620 3450 630 10 day 2200 600* 3355 650 14 days 1545 500 2910 630 21 days 1230 410 2690 V 570 Oxygen bomb 48 hrs. x I

70 C. X 3001bs.. 64 0 460 1870 580 Conn 70 x 404* 3895 6 50 3880 6'50 1 3830 600 I :4175 Y 640 2625 570 3645 630 2210 550 2960 560 1565. 430 2840. 570 1370 350I- 2370 500. 475 I I 500' .1750 ,ao

CURE x 40# 3660 650 3920 650 3660 580 3760' 000 2590 530 3555 590 I 2070, 500 '3100 I 550 1635 420 2490 470 21 days 1185 250 2370 440 Oxygen bomb 48 hrs. x

70 OIX 300 lbs 490 360 1560 460 xamp In this examplethe use of various materials having the above ring constitution is illustratecl. The materials employed as anti oXiclants are as follows (A) Ethylidene di (phenyl amino) ethyl ether. Probable formula is:

Prepared by reacting acetaldehyde with the reaction prodnot of BB dichlor ethyl ether and aniline.

(B) Methylene d-i (alpha naphthyl amino) ethyl ether. Probable formula is: V

I CE; I v

I N 1t 1 I 7 (EH:

(C) Benzyliolene di' (para tolyl amino) ethyl ether. Probable formula is:

Prepared by reacting benzaldehyde with the reaction product of BB dichlor ethyl ether and para toluidine. v

(D) Butylidene 'di (phenyl amino) ethyl ether. Probable formula is:

I '(E) Benz ylidene (ii (alpha naphthyl amino) ethyl ether. I Probable formula is: I

"Prepared by reacting benzaldehyde with the reaction product of BB" dichlor ethyl ether and alpha naphthyl amine. I

7 F) Butylidene oli (alpha naphthyl ami- Prepared by reacting butyl aldehyde with the reaction amine."

e T Benzyhrlehe ai- (phenyl amino) ethyl ether. I Probable formula is: I I I 1 Prepared by product of BB dichlor ethyl ether'and ani 1 ine.

product of BB"dichlor ethyl ether and alpha naphthyl' reacting benzaldehyde with theireaciion' (I-I) Ethylidene 'di (alpha naphthyl amino) ethyl ether. 7 Probable formula is:

Prepared by reacting acetaldehyde with the reaction product of BB dichlor ethyl ether and alpha naphthyl amine.

The above antioxidants were mixed into a stock having the following composition:

Rubber 55.35 Stearic acid 2.00 Carbon black 20.00 Oil 5.00 Zinc oxide 15.00 Sulphur 2.25 Diphenyl guanidine 0.40

The stocks, containing the antioxidants listed above, were mixed from the above base recipe and the quantity of antioxidant used was, in each case 1.

After ealendering into sheets inch in thickness they were vulcanized over a range of cures and subjected to the usual hot oven and oxygen bomb age tests.

The even age test was made at a temperature of 7 0 centigrade and the oxygen bomb test was made at 7 0 centigrade and 300 pounds per square inch oxygen pressure for 48 hours. The results are given in the following tab1es:

Control Days in Oven No antioxidant Ant oxidant A Antioxidant B a Elonga- Elonga- Elonga- Tensxl mm Tonsil mm Tensil tion CURE 50' x 401;

CURE 70 x 40;;

Original 3450 670 3760 620 3540 600 2 days. 3540 000 3685 600 3740 580 7 days 2630 580 3180 570 3095 520 10 days 2100 530 2970 550 2020 500 14 clays- 1805 V 470 2800 520 2700 460 21 days 1205 340 2380 460 2015 410 Oxygen bomb" 070 340 1890 530 1700 490 CURE 90 x Antioxidant C Antioxidant D Antioxidant E Days in oven D 7 E1 Elonga longaenga- Tensil tion Tensil tion Tensil tion CURE x 401* 3680 640 3675 670 3780 660 3500 620 3380 630 3575 620 3460 620 3370 040 3380 010 3075 600 3180 620 3180 010 3000 600 2805 630 2880 600 y 2510 500 2505 600 2500 550 Oxygen bomb 2140 600 1900 000 1000 600 CURE x 403 Original 3760 600 3860 600 3840 640 2 days 3490 590 3320 600 3480 000 7 days--- 3370 600 3375 620 3160 550 10 days" 3120 570 2820 570 2930 520 14 days 2900 530 2805 590 2705 520 21 days 2460 480 2300 530 2220 440 Oxygen bomb 1 1990 540 1810 590 1810 540 CURE 90 x 404 3800 600 3790 050 3870 610 3395 570 3480 590 3400 550 3100 540 3320 580 3430 510 2960 510 3020 540 2880 470 2740 480 2665 520 2640 450 21 days 2320 400 2320 450 2060 350 Oxygen bomb 1810 490 1780 550 1710 480 Antioxidant F Antioxidant G Antioxidant H Days in oven E1 E1. v1

- ongaonga- 11 ongn- Tensil fion Tensil on 'Iensll ti on CURE 504 403 Original..- 3720 650 3815 640 3830 030 2 days 3500 640 3625 630 3720 620 7 days 3540 630 3410 630 3520 010 10 days. 3305 590 3170 620 3375 590 14 days. 3060 600 2815 610 3125 600 21 days 2860 560 2420 660 2500 530 Oxygen bomb- 2195 600 2030 620 2120 600 CURE 70 x 4011 3580 630 3820 040 3705 600 3480 600 3520 600 3300 580 7 days 3360 580 3340 570 3380 550 10 days 3190 540 2880 580 3175 520 14 days 2920 510 2580 520 2085 480 21 days 2610 480 2240 460 2470 440 Oxygen b0mb 2030 550 1835 560 2070 540 CURE 90' x 40? Original 3640 600 3680 000 3540 600 2 days 3395 550 3500 570 3405 530 3260 540 3140 540 3220 490 2815 450 2775 500 2700 44 2580 430 2530 400 2580 420 21 days 2220 360 2200 300 1935 310 Oxygen bomb 1830 490 1740 590 1770 450 The foregoing examples serve to indicate the manner in which the invention may be carried out. The invention,however, is not restricted to such specific examples, as many modifications can be made by one skilled in the art.

In general, the most beneficial effect is obtained by using 0.75% to 1.5% of the antioxicure. Those which have slightacc'elerating' properties, either alone'or in conjunction with the accelerator employed in the stock,

may be added directly to'the rubber stock 7 and the accelerator content adjusted so that the rate of cure remains the same.

It has also been found possible to add the material after the rubber stock has been vuloanized and still obtain appreciable improvement in' the aging qualities" of the stock.

. This may be done by painting or dipping the hyde reactionproduct of a BB diamino di rubber stock with a solution of the desired material and after allowing penetration to take place, to'dry'ofif the surplus solvent.

lVhat I claim is 1. A rubber composition including an aldeethyl ether.

2. A rubber composition including an aide hyde reaction product of a BB diamino di ethyl ether in which one of the hydrogen atoms of each amino group is replaced by an aryl. hydrocarbon residue.

3. A rubber composition including an aldehyde reaction product of a BB diamino di ethyl ether in which one of the hydrogen atoms of each amino group is replaced by an alkyl hydrocarbon residue.

4. A rubber composition including an aldehyde reaction product of-a BB diamino di ethyl ether in which one of the hydrogen atoms of one amine group is replaced by an aryl hydrocarbon residue and one of the hydrogen atoms of the other amino group is replaced by an alkyl hydrocarbon residue. v

A rubber composition including an aldehyde reaction product of a BB diamino di ethyl ether in which each nitrogen atom is attached to an alkyl and an aryl hydrocarbon residue. 7 p r V 6. A rubber composition including an aldehyde reaction product of a diaryl substituted BB diamino di ethyl ether.

7. A rubber composition including an aldehyde reaction product of a'dialkyl substituted BB. diamino di ethyl ether.

8, A rubber composition including an aldehyde reaction product of the material obtained by heating one mol'of BB dichlor di ethyl ether with at least two mols of a compound containing a primary amino group.

.' 9. A- rubber composition including an aldehyde reaction product of the material from which morpholine derivatives have been re-v moved obtained by heating one mollof BB dichlor di ethyl ether with at least two mols of a compound containing a primary amino group.

10. A rubber composition including an aldehyde reaction product of the material obtained by heating one mol of BB dichlor di ethyl (ether with; at least twomols of a primary aromatic amine. v

11. Arubber composition including an aldehyde reaction product of the material from which morpholine derivatives have been removed, obtained by heating one mol of BB dichlor di ethyl ether with at least two mols of a primary aromatic amine.

12. A rubber composition including an aldehyde reaction product of the material ob tained by heating o-nemol of BB dichlor di ethyl ether with at least'two mols of a secondary aromatic amine.

13. A rubber composition including an al- A dehyde reaction'product of the material from which morpholine derivatives have been removed, obtained by heating one mol of BB dichlor di ethyl ether with at least two mols x of a secondary aromatic amine.

14. A rubber composition includingbutylidene BB di (phenyl amino) di ethyl ether.

15. A rubber composition including an aldehyde reaction product of the material obtained by heating one mol of BB dichlor di ethyl ether with at least two mols of aniline.

16. A rubber composition including the butylaldehyde reaction product of the material obtained by heating one mol of BB dichlor di ethyl ether with at'least two .mols of aniline.

'17. A rubber composition including an aldehyde reaction product of the material, from which N phenyl morpholine has been removed, obtained by heating one mol of BB gen atoms attached to the carbon atom, which is attachedto both nitrogen atoms, may be replaced by alkyl, aryl and alkyl-aryl radi 1 cals. V p I V 19. A process'for inhibiting oxidation of rubbery or a rubber-like compound which comprisescombining with said material a substance having'a characteristic group as follows:

H2 N CH2/ In testimony whereof, I affix mysighw m ture.

HAROLD A. MORTON.

Certificate of Correction Patent N 0. 1,847,974.

HAROLD A. MORTON It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows Page 3, strike out the boxed table of headings between lines 20 and 25, and insert instead the following- OompoundB- l. 5% Antioxidant Tonsil Elongation Tensll Elongation and that the said Letters Patent should be read with this correction therein that the same may conform'to the record of the case in the Patent Office.

This certificate supersedes Certificate of Correction issued May 10, 1932.

Signed and sealed this 7th day of June, A. D. 1932'.

[SEAL] M. J. MOORE,

Acting Uommissz'oner 0 f Patents. 

